Cartridge and chamber for firearm

ABSTRACT

A cartridge and a chamber for a firearm adapted to fire a bullet with an outside diameter of about 0.223″ (also known as a 223 round). The cartridge has an axis, a neck, a shoulder, a body, and an extraction groove. The chamber of the present invention is provided for the cartridge, described above. The chamber has an axis, a neck bore, a shoulder bore, and a body bore. The shoulder and the shoulder bore may be formed at an angle where the angle is about 28°, ±3° with respect to the axis of the cartridge or chamber. Upon firing a firearm equipped with the cartridge and chamber of the present invention, the bullet is capable of reaching a velocity of greater than about 2,500 fps.

CROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/419,537, filed Oct. 21, 2002.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a cartridge and a chamber for a firearm, in particular a cartridge and chamber for a handgun or rifle adapted to fire a bullet with an outside diameter of about 0.223 inches (″).

[0004] 2. Description of Related Art

[0005] Prior art firearms which fire bullets with an outside diameter of about 0.223″ often require the use of a relatively large firearm with a relatively large cartridge and chamber. Specifically, the diameter of the cartridge and chamber is often greater than 0.400″ and/or the length of the cartridge is often greater than 1.000″. Also, the neck and shoulder of prior art cartridges and chambers are typically provided at such an angle that the cartridge does not feed properly from the magazine into the barrel. These problems result in a slow round. In other words, it takes a comparatively long time for the round to advance from the magazine to the barrel upon pulling the trigger. Further, the dimensions of the cartridge and chamber result in wear and tear on the firearm. For instance, upon firing, some prior art cartridges are found to peen or damage the metal on the locking lugs. In addition, the prior art chambers and cartridge are typically capable of achieving a limited bullet velocity.

[0006] A variety of cartridges and chambers for 0.223″ bullets have been proposed, all of which have one or more of the problems identified above. U.S. Pat. No. 5,033,386, issued Jul. 23, 1991 to Vatsvog, describes a composite cartridge for a 0.223 caliber high velocity rifle. The outside diameter of the Vatsvog cartridge at its widest point is 0.398″. The length and shoulder angle of the Vatsvog cartridge are not discussed.

[0007] U.S. Pat. No. 5,970,879 issued Oct. 26, 1999 and U.S. Pat. No. 6,354,221 B1 issued Mar. 12, 2002, both to Jamison, describe high-power firearm cartridges. Both Jamison patents are directed to a cartridge in a first embodiment with an overall length L of about 2.2″, a shoulder angle of approximately 35°, and a diameter D of between about 0.53 and 0.54″, and a cartridge in a second embodiment with an overall length L of about 1.7″, a shoulder angle of at least 30° but less than 40°, and most preferably approximately 35°, and a diameter D of at least about 0.45″, and preferably 0.533″. Independent claims 1 and 3 of the '879 patent are specifically limited to a cartridge with a diameter of at least 0.53″ and 0.45″, respectively.

[0008] Independent claim 2 of the '879 patent discloses a cartridge longer than 1.25″, since the claim requires a first portion having an outside diameter at a location 1.25″ from the first end. The independent claims of the '221 patent disclose similar limitations. Cartridges with a shorter length, a smaller shoulder angle, or a smaller diameter are not taught or suggested by the Jamison patents.

[0009] U.S. Pat. No. 6,293,203 By, issued Sep. 25, 2001, to Alexander et al., describes a cartridge for a 5.56 millimeter (mm) (0.224″) projectile. Although the independent claims of the Alexander patent recite a limit velocity not less than 518 meters per second (m/s), or 1,700 feet per second (fps), FIG. 5 of the Alexander patent shows a maximum limit velocity of about 2,000 fps. The angle y of the Alexander patent is not claimed, but is disclosed to be 32° in the preferred embodiment. The preferred embodiment of Alexander has a cartridge with an outside diameter A of 10.80 mm (0.425″). There is no teaching or suggestion in Alexander for a limit velocity of greater than 2,000 fps, an angle of less than 32°, or an outside diameter of less than 10.80 mm (0.425″).

[0010] None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.

SUMARY OF THE INVENTION

[0011] The present invention is directed to a cartridge and a chamber for a firearm. The firearm may be a handgun or a rifle. Specifically, the cartridge and chamber are adapted for use with a firearm adapted to fire a bullet with an outside diameter of about 0.223″ (also known as a 223 round). The cartridge comprises an axis, a neck, a shoulder, a body, and an extraction groove. The cartridge has a total length between 0.870 and 1.000″. The first body outside diameter, which is the diameter of the body at its widest point, is about 0.375″, ±0.005″. The shoulder may be formed at an angle between the body and the neck where the angle is about 28°, ±3°, with respect to the axis of the cartridge. The total length, the first body outside diameter and the shoulder angle of the cartridge of the present invention are each smaller than many prior art cartridges. Upon firing a firearm equipped with the cartridge and chamber of the present invention, the bullet is capable of reaching a velocity of greater than about 2,500 fps.

[0012] The chamber of the present invention is provided for the cartridge, described above, where the cartridge has a total length between 0.870 and 1.000″. The chamber is adapted for use with a handgun or rifle with a barrel bore adapted to fit the bullet with an outside diameter of 0.223″. The barrel bore may be provided with a region adapted to fit the ogive of the bullet. The chamber comprises an axis, a neck bore, a shoulder bore, and a body bore. The first body bore inside diameter, which is the diameter of the body bore at its widest point, is about 0.376″, ±0.005″. The shoulder bore may be formed at an angle between the body bore and the neck bore where the angle is about 28°, ±3° with respect to the axis of the chamber. The total length, first body bore outside diameter and shoulder bore angle of the chamber of the present invention are each smaller than many prior art cartridges. Upon firing a firearm equipped with the cartridge and chamber of the present invention, the bullet is capable of reaching a velocity of greater than about 2,500 fps.

[0013] Accordingly, it is a principal object of the invention to provide a cartridge for a bullet with an outside diameter of

[0014] It is another object of the invention to provide a chamber for a cartridge for a bullet with an outside diameter of about 0.223″.

[0015] It is an object of the invention to provide improved elements and arrangements thereof in an apparatus for the purposes described which is inexpensive, dependable and fully effective in accomplishing its intended purposes.

[0016] These and other objects of the present invention will become readily apparent upon further review of the following specification and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The sole FIGURE is a side view of a cartridge and a chamber for a firearm according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] As shown in the sole FIGURE, the present invention is directed to a cartridge 10 and a chamber 100 for a firearm. The firearm may be a handgun or a rifle, as described in detail below. Specifically, the cartridge 10 and chamber 100 are adapted for use with a firearm adapted to fire a bullet 200 with an outside diameter D₁ of about 0.223″ (also known as a 223 round).

[0019] The cartridge 10 comprises an axis 20, a neck 30, a shoulder 40, a body 50, and an extraction groove 60. The cartridge 10 has a total length L₃ that may be between 0.870 and 1.000″. The cartridge 10 is typically made of brass, but may also be made of iron, plastic, or other suitable types of metal. One advantage to using a brass cartridge is that, after firing, the cartridge may be resized and reused.

[0020] The body 50 is hollow and generally cylindrical with a closed end opposite the bullet 200. The body 50 comprises a first body outside diameter D₄, a second body outside diameter D₃, a body length L₁, and the extraction groove 60. The first body outside diameter D₄, which is the diameter of the body 50 at its widest point, is about 0.375″, ±0.005″. The second body outside diameter D₃ is less than or equal to the first body outside diameter D₄. In other words, the body 50 may be cylindrical with ends that are of the same diameter, or the body 50 may be tapered. If the body 50 is to be tapered, the second body outside diameter D₃ may be about 0.367″, ±0.005″. The ratio of the first body outside diameter D₄ to the outside diameter D₁ of the bullet 200 is between 1.66 to 1 and 1.70 to 1. In a preferred embodiment of the invention, the ratio is 1.67 to 1.

[0021] The cartridge 10 is formed using a customized sizing die (not shown) provided in a corresponding size and shape which is adapted to form the cartridge 10 as described herein.

[0022] The body length L₁ is measured from the terminal end of the body 50 on the end opposite the bullet 200 (left side of the FIGURE) to the intersection of the body 50 with the shoulder 40. The body length L₁ is between 0.670 and 0.800″. In a first preferred embodiment of the invention, identified by the inventor as the PK224 cartridge, the body length L₁ is about 0.675″, ±0.005″, the axial length L₂ of the body 50 and the shoulder 40 is about 0.775″, ±0.005″, and total length L₃ is about 0.875″. In a second preferred embodiment of the invention, identified by the inventor as the PK2224 cartridge, the body length L₁ is about 0.735″, ±0.005″, the axial length L₂ of the body 50 and the shoulder 40 is about 0.835″, ±0.005″, and total length L₃ is about 0.935″, ±0.005″. In a third preferred embodiment of the invention, identified by the inventor as the PK224S or PK224 Super cartridge, the body length L₁ is about 0.795″, ±0.005″, the axial length L₂ of the body 50 and the shoulder 40 is about 0.895″, ±0.005″, and total length L₃ is about 0.995″, ±0.005″.

[0023] The neck 30 is hollow and generally cylindrical provided on the terminal end of the cartridge 10 adjacent to the bullet 200 right side of the FIGURE). The neck 30 has a neck outside diameter D₂ of about 0.260″, ±0.005″. The neck 30 is adapted to fit the bullet 200.

[0024] The shoulder 40 is hollow and conical provided between the body 50 and the neck 30. The shoulder 40 may be formed at an angle α x between the body 50 and the neck 30 where the angle α x is about 28°, ±3°, with respect to the axis 20 of the cartridge 10. The angle α x of the shoulder 40 is shallower than many prior art cartridges. The shallower angle of the present invention is desirable in that it promotes proper feeding of the cartridge 10 from the magazine of the firearm and reduces damage to the metal on the locking lugs of the firearm.

[0025] For the sake of comparison, a standard 9 mm handgun is capable of firing a bullet at about 1,000 fps. Upon firing a handgun provided with the cartridge 10 of the present invention as described above, the bullet 200, for example, a 35 grain 0.223″ bullet, is capable of reaching a velocity of greater than about 2,500 fps. When used with a rifle, the bullet 200 is capable of reaching a velocity of greater than about 3,000 fps.

[0026] The present invention is also directed to a chamber 100 for the cartridge 10 (described above) with a total length L₃ between 0.870 and 1.000″ for a bullet 200 with an outside diameter of about 0.223″. The chamber 100 is adapted for use with a handgun or rifle with a barrel bore 120 adapted to fit the bullet 200. The barrel bore 120 has an inside diameter D₅ of about 0.224″.

[0027] The barrel bore 120 may be provided with a region 130 adapted to fit the ogive of the bullet 200. The chamber 100 comprises an axis 110, a neck bore 140, a shoulder bore 150, and a body bore 160.

[0028] The chamber 100 is formed using a customized chamber reamer (not shown) provided in a corresponding size and shape that is adapted to form the chamber 100 as described herein. The chamber reamer may be provided with five or six flukes. The flukes of the chamber reamer may be straight.

[0029] The body bore 160 is generally cylindrical with open ends. The body bore 160 comprises a first body bore inside diameter D₈, a second body bore inside diameter D₇, and a body bore length L₄ adapted to receive the cartridge 10. The first body bore inside diameter D₈, which is the diameter of the body bore 160 at its widest point, is about 0.376″, ±0.005″. The second body bore inside diameter D₇ is less than or equal to the first body bore inside diameter D₈. In other words, the body bore 160 may be cylindrical with ends that are of the same diameter, or the body bore 160 may be tapered. If the body bore 160 is to be tapered, the second body bore inside diameter D₇ may be about 0.368″, 0.005″. The ratio of the first body bore inside diameter D₈ to the outside diameter D1 of the bullet 200 is between 1.65 to 1 and 1.70 to 1. In a preferred embodiment of the invention, the ratio is 1.68 to 1.

[0030] The body bore length L₄ is measured from the terminal end of the body bore 160 on the end opposite the bullet 200 (left side of the FIGURE) to the intersection of the body bore 160 with the shoulder bore 150. The body bore length L₄ is sufficient in length to receive the cartridge 10, which as noted above, has a cartridge body length L₁ between 0.670 and 0.800″. In a first preferred embodiment of the invention, the chamber 100 is adapted to receive the PK224 cartridge, and the body bore length L₄ is adapted to receive the cartridge 10 where the cartridge body length L₁ is about 0.675″, ±0.005″, the axial length L₂ of the body 50 and the shoulder 40 is about 0.775″, ±0.005″, and total length L₃ is about 0.875″. In a second preferred embodiment of the invention, the chamber 100 is adapted to receive the PK2224 cartridge, and the body bore length L₄ is adapted to receive the cartridge 10 where the cartridge body length L₁ is about 0.735″, ±0.005″, the axial length L₂ of the body 50 and the shoulder 40 is about 0.835″, +0.005″, and total length L₃ is about 0.935″, ±0.005″. In a third preferred embodiment of the invention, the chamber 100 is adapted to receive the PK224S cartridge, and the body bore length L₄ is adapted to receive the cartridge 10 where the cartridge body length L1 is about 0.795″, ±0.005″, the axial length L₂ of the body 50 and the shoulder 40 is about 0.895″, ±0.005″, and total length L₃ is about 0.995″, ±0.005″.

[0031] The neck bore 140 is generally cylindrical provided on the end of the chamber 100 adjacent to the bullet 200 (right side of the FIGURE). The neck bore 140 has a neck bore inside diameter D₆ of about 0.261″, ±0.005″.

[0032] The shoulder bore 150 is conical and provided between the body bore 160 and the neck bore 140. The shoulder bore 150 may be formed at an angle α between the body bore 160 and the neck bore 140 where the angle α is about 28°, ±3° with respect to the axis 110 of the chamber 100. The angle α of the shoulder bore 150 is shallower than many prior art chambers. The shallower angle of the present invention is desirable in that it promotes proper feeding of the cartridge 10 from the magazine into the chamber 100 of the firearm and reduces damage to the metal on the locking lugs of the firearm.

[0033] As noted above, the chamber 100 is adapted for use with the cartridge 10. Likewise, as described in detail above, the chamber 100 is adapted for use with a variety of handguns and rifles. A standard 9 mm handgun is capable of firing a bullet at about 1,000 fps. When using a firearm equipped with the chamber 100 and cartridge 10 of the present invention, the bullet 200 is capable of reaching a velocity of greater than about 2,500 fps. When using a rifle equipped with the chamber 100 and cartridge 10 of the present invention, the bullet 200 is capable of reaching a velocity of greater than about 3,000 fps.

[0034] The cartridge 10 and chamber 100 of the present invention may be adapted for use with any handgun. For example, the cartridge 10 is adapted for use with the following handguns: Colt 2000, Ruger P85, Ruger P95, military Beretta 92, Glock 17, and a 45 caliber handgun chambered to fire a 223 round. A standard double stack magazine for a 9 mm handgun accepts the cartridge 10 of the present invention without modification to the magazine. The cartridge 10 and chamber 100 of the present invention result in a significantly faster round when compared to the prior art. In other words, it takes a comparatively short time for the round of the present invention to advance from the magazine to the barrel upon pulling the trigger. In using the cartridge 10 and chamber 100 of the present invention with a 9 mm handgun, there is less recoil, less muzzle jump, better control, the user is back on target quicker, and the handgun is generally much faster as compared to a conventional 9 mm handgun.

[0035] The cartridge 10 and chamber 100 of the present invention may also be adapted for use with any rifle that accepts a 223 round. For example, the cartridge 10 and chamber 100 of the present invention have been used with a Colt civilian model AR15 rifle that was converted to a pump type rifle. The AR15 is LITMAN LAW similar to a military M16 rifle. A standard AR15 is chambered for the Remington 223. When used with a rifle, the cartridge 10 and chamber 100 of the present invention are capable of firing a bullet at about 3,000 fps. Accuracy is also improved by using the cartridge 10 and chamber 100 of the present invention. For example, at 300 feet, the inventor was able to place 7 rounds into a ⅜″ shot pattern.

[0036] It is to be understood that the present invention is not limited to the sole embodiments described above, but encompasses any and all embodiments within the scope of the following claims. 

I claim:
 1. A cartridge for a bullet with an outside diameter of about 0.223″, the cartridge comprising: an axis; a body, said body comprising: a first body outside diameter, wherein said first body outside diameter is about 0.375″; a second body outside diameter which is less than or equal to the first body outside diameter; a total length, wherein said total length is between 0.870 and 1.000″; and an extraction groove; a neck with a neck outside diameter, wherein said neck outside diameter is about 0.260″, and wherein said neck is adapted to fit the bullet; and a shoulder between said body and said neck, wherein said shoulder is formed at an angle between said body and said neck, wherein said angle is about 28° with respect to said axis.
 2. A cartridge for a bullet with an outside diameter of about 0.223″, the cartridge comprising: an axis; a body, said body comprising: a first body outside diameter, wherein said first body outside diameter is about 0.375″; a second body outside diameter which is less than or equal to the first body outside diameter; a total length, wherein said total length is between 0.870 and 1.000″; and an extraction groove; a neck with a neck outside diameter, wherein said neck outside diameter is about 0.260″, and wherein said neck is adapted to fit the bullet; and a shoulder between said body and said neck, wherein said shoulder is formed at a predetermined angle relative to said axis between said body and said neck such that upon firing, the bullet is capable of reaching a velocity of greater than about 2,500 fps.
 3. A chamber for a cartridge with a total length between 0.870 and 1.000″ for a bullet with an outside diameter of about 0.223″, the chamber comprising: an axis; a body bore, said body comprising: a first body bore inside diameter, wherein said first body bore inside diameter is about 0.376″; a second body bore inside diameter which is less than or equal to the first body bore inside diameter; and a body bore length adapted to receive the cartridge; a neck bore with a neck bore inside diameter, wherein said neck bore inside diameter is about 0.261″; a shoulder bore between said body bore and said neck bore, wherein said shoulder bore is formed at an angle between said body bore and said neck bore, wherein said angle is about 28° with respect to said axis.
 4. The cartridge according to claim 1, wherein said cartridge is adapted for use with a handgun.
 5. The cartridge according to claim 1, wherein said cartridge is adapted for use with a rifle.
 6. The cartridge according to claim 1, wherein, upon firing, the bullet is capable of reaching a velocity of greater than about 2,500 fps.
 7. The cartridge according to claim 1, wherein, upon firing, the bullet is capable of reaching a velocity of greater than about 3,000 fps.
 8. The cartridge according to claim 1, wherein said total length is about 0.875″.
 9. The cartridge according to claim 1, wherein said body length is about 0.935″.
 10. The cartridge according to claim 1, wherein said body length is about 0.995″.
 11. The cartridge according to claim 1, wherein said second body outside diameter is about 0.367″.
 12. The chamber according to claim 3, wherein said chamber is adapted for use with a handgun.
 13. The chamber according to claim 3, wherein said chamber is adapted for use with a rifle.
 14. The chamber according to claim 3, wherein, upon firing, the bullet is capable of reaching a velocity of greater than about 2,500 fps.
 15. The chamber according to claim 3, wherein, upon firing, the bullet is capable of reaching a velocity of greater than about 3,000 fps.
 16. The chamber according to claim 3, wherein said body bore length is adapted to receive the cartridge wherein the total length is about 0.875″.
 17. The chamber according to claim 3, wherein said body length is adapted to receive the cartridge wherein the total length is about 0.935″.
 18. The chamber according to claim 3, wherein said body length is adapted to receive the cartridge wherein the total length is about 0.995″.
 19. The chamber according to claim 3, wherein said second body bore inside diameter is about 0.368″. 